A. Field
The present invention concerns a compressor device.
B. Related Technology
More particularly the present invention concerns a compressor device of the variable speed type that basically consists of a case or housing with a compressor element therein that is powered by a variable speed motor with a fixed set maximum number of revolutions for the compressor, an air cooling blower which sucks air from the environment via an inlet and blows it via an exhaust through this case back to the environment, and a separate cooling circuit with a cooling medium for cooling of the gas which has been compressed by the compressor or cooling compressed air from the compressor.
Common compressor devices are generally designed in order to be able to function in certain conditions of maximum environmental temperature, these conditions are named as the nominal working conditions.
In the case that the limits of the nominal environmental conditions are exceeded, then, the good working of the compressor device can no longer be guaranteed and that will lead to unpredictable stoppages of the compressor device.
In such a case it is presently the practice to use a compressor device which is over sized and therefore generates less heat than a smaller compressor device in the same conditions or a compressor device which is working at its maximum capacity by limiting the set maximum allowed number of revolutions of the compressor, for example, through the application of a transmission with a smaller transmission ratio than for nominal conditions. Therefore an extra thermal reserve is created, that can used in order to counter act the higher environmental temperature.
This has the disadvantage that a bigger investment is necessary for the compressor device and that the compressor device is not optimally utilized under all nominal conditions with the result that there is a loss of performance in nominal conditions.